Machine for bending pipes



June 5, 1951 P. H. wooDs 2,555,723

MACHINE FOR BENDING PIPES June 5, 1951 P. H. wooDs MACHINE FOR BENDING PIPEs 5 Sheets-Sheet 2 Filed Sept. 23, 1949 June 5, 1951 l P. H. wooDs 2,555,723

MACHINE FOR BENDING PIPES Filed sept. 23, 1949 s sheets-sheet s 5 d 7. R. wu F 0 IH w inw YWithin the machine itself.

torque between the machine and the floor or Patented June 5, 1951 UNITED STATES rATENT OFFICE MACHINE FOR BENDING PIPES Philip H. Woods, Raleigh, N. C.

Application September 23, 1949, Serial No. 117,460

6 Claims. 1

The present invention relates to machines for bending hollow or solid metallic rod stock. While the machine is of general universal application where it is desired to bend any type of stock in an are, its novel construction resulting in a design that operates close to the floor without need for anchoring thereto and which is structurally strong but yet relatively light in weight makes the improved machine especially suited for portable use for on-the-job bending of copper or iron tubing in the fabrication of iioor type radiant heating coils from the stock. The completed iioor coils usually consist of several lengths of the tubular stock joined together and containing a large number of I180 bends. Warm Water is then circulated through the coils as a heating medium.

When making up the coil, it is preferable to begin at one side ofthe floor, placing the lengths of tubular stock in place progressively, joining the ends, and making the 180 bends one after the other until the other side of the floor is reached. Such procedure calls 'for a pipe bending machine essentially portable, i. e. light in weight, that can be easily carried about the job from place to place when Vthe bends are to be made. Moreover the machine must be of such design that it can operate close to the floor to the end that the coil will be left in proper position without further handling when all bends have been made, i. e. each bend must be made close to the iioor so as not to disturb the run of pipingbehind the machine.

Another object of the invention is to provide a stock bending machine having a reversible drive thereby enabling the machine to be `powered in either direction of operation by the conventional portable drill tool motor which is capable of rotating in only one direction.

Yet another object is to provide a stock bending machine in which all forces and counter forces, torques and counter torques are effected No external force or other base upon which it rests is thus necessary to maintain the same stationary While in use and consequently the machine has a very high strength/weight ratio making it possible to operate on comparatively heavy Stock with a relatively light weight machine.

A stillfurther object of the invention is to provide a stoel; bending machine that is easily and Yquickly adaptable to operate on various sizes and configurations 'of stock.

The foregoing aswell as other objects and advantages inherent inthe invention will become more readily apparent from the following detaileddescription of a preferred, structural em- Fig. 1 is a top plan of the improved machine;

Fig. 2 is a side elevation;

Figs. 3 and 4 are end elevations;

Fig. 5 is a vertical section on line 5-5 of Fig. 1

Figs. 6 and 7 are horizontal sections on lines 6 6 and 'l-l of Fig. 5; and

Fig. 8 is a fragmentary horizontal sectional detail of the block and sweep arm.

Referring now to the drawings, the bending machine is seen to be comprised of two principal components, these being a stationary and generally rounded block member I and a pair of sweep arm members 2, 3 located adjacent the upper and lower faces of the block and` pivoted on the latter, the arms being coupled at their outer ends by a dog 4 between which and the rounded periphery of the block the desired bend in the pipe 5 (outlined in broken lines) is formed.

The stationary block I has an arcuate periphery 6 with a center of radius coincident with the axis -.r (see Fig. 5), and which contains a groove l constituting one of the two forming surfaces for the stock. The configuration of groove l in the plane of its radius will of course be determined by the cross-section of the stock to be bent. The present embodiment is designed speciiically for bending pipe or other like'stock of circular cross-section and hence groove 'l is semi-circular- Block I is also provided with an arcuate slot 3 on the same radius as groove 1 and one edge of the slot is toothed to provide an internal arcuate rack gear 9.

The upper and lower sweep arms 2, 3 are pivotally connected to block I for rotation about vertical axis -rr by means of sleeve type bearings, the sleeves I8 being carried by the arms, and the bearing shafts II being carried by block I.

Upstanding upon the upper arm 2 and forming an integral part thereof is a case I2 that encloses compound reduction gearing for transmitting power applied to one of three input shafts I3, I4, I5 to the output shaft I6 in order to eifect a rotation of the arms 2, 3 about the block I.

The two input shafts I3, I4 located generally centrally of the block member, which project vertically upward through and are journalied in a common boss I2C on cover Ia of case Ig, are provided at their upper ends with hexagonal sockets Il, IS respectively to receive a cornplementary configured arbor I9 that is adapted to be chucked at 20 to conventional portable motor 2i. Meshed input pinions 23, 24 are pro vided at the lower ends of shafts i3, I and pinion 23 meshes with a large gear -25 secured to the third input shaft i5 that is journalled in bearing sleeves carried by the cover ic and bottom wall i217 of the gear case. A hexagonal socket/26 is securedto the upper endof `shaft i5 `rigidity forY the posts.

and a pinion gear 21 secured to the lower end thereof meshes with a large gear 28 secured to the upper end of the output shaft I that is journalled in vertically aligned bearing sleeves carried by the upper and lower sweep arms 2, 3. Output shaft I6 extends through the arcuate slot 8 in block I and carries a pinion gear 29 that meshes with the internal rack gear 9.

Motor 2l is adapted to be supported by the cover 12a of the gear case above and in general alignment with the input shafts I3, I4 and for this purpose two upright posts 32, 33 are provided respectively at the front and rear of the cover. The lower ends or these are received in recessed bosses 34 in the cover and struts 35 at leach side of the posts anchored by capscrews 36 that extend through cover IZa into threaded recesses in the case side walls provide vertical The upper ends of posts 32, 33 are internally threaded at 31 to receive threaded studs 38, 39 that carry yokes 43, il for supporting the motor handles 43, 44. Yoke 43' is of the double type providing two cradles 43a, 40h for the handle li3, and yoke 4i has but one cradle 4I@ to receive the oppositely extending handle 44 in which is incorporated a trigger i5 .for turning the motor switch on and off.

Yokes and 4I are centered along the central longitudinal axis of the machine. Hence cradle dia is centered along such axis while cradles lic, 451) are on each side thereof. Thus when handle 43 is carried by cradle 43a, the motor chuck 2@ will be aligned with socket Il and when carried by cradle 4%, the chuck will be aligned with socket I8.

For supporting the block I on a iioor or the like, a base consisting of two legs 46, 4'! arranged at right angles in the form of a cross is utilized. A screw 48 extends through the legs 55, d? at the center of the cross into the lower end of the bearing shaft II to support the block at this point, and another screw 49 extends through leg lil into the lower end of a yoke 5E projecting from the rear side of the block I.

Yoke serves as the support for an anchor 5I that secures the stock in place during the bending operation. Anchor 5I includes a hook 52 adapted to t over the stock 5, a threaded stud 53 to which hook 52 is pivotally connected and a yoke 54 into which stud 53 is threaded, the yoke 54 being detachably fastened to yoke 55 by means of two sets of complementary pins and apertures 55, 53 provided on the yoke arms.

The improved machine can be used for bending several differently sized rods to several different radii. As illustrated in Figs. 1-7 the machine is set up to bend pipe stock 5 of outside diameter d about a radius r. For such purpose, a half round filler band 5l of internal diameter d and outside diameter d is employed, the band being seated in the half round groove rI of diameter d' provided in the periphery of block I and secured thereto by screws 58.

Confronting the filler band 5l is another half round groove 53 of diameter d provided in one face of the triangular dog 4 located between the outer end portions ofsweep arms 2, 3 and adapted to be connected to the latter by means of a headed through pin BI that is selectively engageable with any of three sets 62-64 of vertically As illus-- sweep arms and dog are caused to move around the block.

For bending larger pipe stock having an outside diameter d' corresponding to the diameter of the groove 'l Without the filler band 57, the latter is removedfrom the block I and dog 4 rotated to bring groove 65 in a second face thereof and having the same diameter d as groove 'l into confronting relation with groove l. The larger pipe will of course be bent to the same radius r.

For bending pipe having an outside diameter d to a larger radius than r, a ller band ES as shown in Fig. 8 is used, this band having an internal half round rib 61 adapted to be seated in groove 'IV and an external half round groove 68 is the same diameter as pipe 5. Filler band 55 can be secured to block I in the same manner as band 5l and ythe `proper groove in the dog to be used will of course be groove 59. However in this case, dog 4 will be moved outwardly of the sweep arms to the next set of apertures 63, the distance between the centers of aperture sets 52, 63 corresponding of course to the change in radius.

For bending even larger sized pipe the third side of dog 4 is seen to be provided with a groove 53 larger Ythan the other two and would cooperate with a ller band similar to band 56 in Fig. 8 and provided with a groove of the same size as groove 53.

Operation Assuming the sweep arms 2, 3 to be in a position 99 clockwise from the o ne illustrated in the drawings, the pipe 5 is run between dog 4 and groove l and through hook 52 to the place where the bend is to be made. Motor 2l is then put in place with the motor shaft chucked to socket Il and turned on by actuating switch control trigger 45. The power input to pinion 23 is f; transmitted through the compound reduction gearing to the output pinion 29 causing the latter to move counter clockwise in an arc along the internal rack gear'B. Since output pinion 29 is mounted on shaft I6 and the latter is journalled in sweep arms 2, 3, the arms will of course be rotated slowly about block I inra counter clockwise direction causing the pipe to be bent around the block up to a maximum bend of A lug 'lil at one side of block I serves as a stop for the sweep arms when moving counter clockwise, and a similar lug at the other side of the block serves a like purpose when the arms rotate clockwise. The arms 2, 3 can then be run back to the starting position forv a repeat operation by shifting motor 2i over to the other socket I8. This of course reverses Vthe direction of the drive.

If a clockwise bend as measured from the anchor point is required inthe pipe, the anchor 5I can be rotated on its pivotal support to the other side of the block and the pipe anchored on such side in which case the driving torque would then be through socket I8.

For comparatively light stock a higher` speed operation by hand is possible in which case the motor can be replaced by a hand crank II thatengages socket 25 to rotate shaft I5 and gears 25 and 2l directly.

When motor 2| is used to drive the sweep arms 2, 3, the necessary counter torque to prevent relative movement between block I and the arms is developed internally in the machine by virtue of the fact that motor 2| is carried by the sweep arms. Thus the block i does not have to be bolted to the floor. When the hand crank 'II is however used to rotate the sweep arms, there will be a torque between the floor or other support and the block but this can be absorbed by securing the block to the support such as by bolting down the arms 46, 41 or by an application of a staying pressure from the foot of the operator.

In conclusion, I wish it to be understood that while the particular machine construction described and illustrated is preferred, various changes in the structural details and arrangement of component parts may be made by others without however departing from the spirt and scope of the invention as defined in the appended claims.

I claim:

1. In a stock bending machine, the combination comprising a stationary block member having an arcuate periphery, a sweep arm pivoted to said block member for rotation about the periphery thereof on an axis coincident with the center of radius of the periphery, reduction gearing carried by said sweep arm, said gearing including a pair of meshed input pinions each provided with a drive shaft, a ring gear meshed with one of said input pinions and an output pinion meshed with a stationary arcuate rack gear provided on said block member, means for supporting a motor on said sweep arm to provide a driving torque to either of said drive shafts, and a dog carried by said sweep arm cooperative with the periphery of said block member.

2. In a stock bending machine, the combination comprising a stationary block` member having an arcuate periphery, a sweep arm pivoted to said block member for rotation about the periphery thereof on an axis coincident with the center of radius of the periphery, reduction gearing carried by said sweep arm, said gearing including a pair of meshed input pinions each provided with a drive shaft, a ring gear meshed with one of said input pinions and an output pinion meshed with a stationary arcuate internal rack gear provided on said block member, means for supporting a motor on said sweep arm to provide a driving torque to either of said drive shafts, and a dog carried by said sweep arm cooperative with the periphery of said block member.

3. A portable stock bending machine comprising, a stationary block adapted to rest in a horizontal position closely adjacent the noor, said block having an external arcuate grooved periphery and a stationary arcuate rack gear arranged internal to and concentric with said periphery, upper and lower sweep arms disposed adjacent the upper and lower faces respectively of said block and extending beyond the periphery thereof, means pivotally mounting said arms on said block for rotation on a common vertical axis coincident with the center of radius of said periphery, a dog disposed between and secured to both of said sweep arms beyond the periphery of said block, an output shaft including a pinion located between said sweep arms and meshed with said internal rack gear, vertically aligned bearing means in said upper and lower sweep arms journalling said output shaft, an input shaft, and reduction gearing extending between said input and output shafts, said input shaft and reduction gearing being carried by said upper sweep arm.

4. A portable stock bending machine comprising, a stationary block member adapted to rest in a horizontal position closely adjacent the floor, said block member having an external arcuate grooved periphery and a stationary arcuate rack gear arranged internal to and concentric with said periphery, upper and lower sweep arm members disposed adjacent the upper and lower faces respectively of said block member and extending beyond the periphery thereof, means pivotally mounting said arm members on said block member for rotation on a common vertical axis coincident with the center of radius of said periphery, a dog disposed between and secured to both of said sweep arm members beyond the periphery of said block member, an output shaft including a pinion located between said sweep arm members and meshed with said internal rack gear, vertically aligned bearing means in said upper and lower sweep arm members journalling said output shaft, an input shaft rotatable on a vertical axis located generally centrally of said block member, reduction gearing extending between said input and output shafts, said input shaft and reduction gearing being carried by said upper sweep arm member, and a motor carried by one of said members, said motor being disposed above and in general alignment with and coupled to said input shaft.

5. A portable bending machine as defined in claim 4 wherein said motor is carried by said -upper sweep arm member.

6. A portable stock bending machine comprising, a stationary block adapted to rest in a horizontal position adjacent the floor, said block having an external arcuate grooved periphery, upper and lower sweep arms disposed adjacent the upper and lower faces respectively of said block and extending beyond the periphery thereof, means pivotally mounting said arms on said blocl: for rotation on a common vertical axis coincident with the center of radius of said periphery, a dog disposed between and secured to both of said sweep arms beyond the periphery of said block, said block also being provided with an arcuate toothed slot constituting a rack gear arranged concentrically with the periphery thereof and disposed between said periphery and the axis of rotation of said sweep arms, an output shaft including a pinion located between said sweep arms and meshed with said rack gear, vertically aligned bearing means in said upper and lower sweep arms journalling said output shaft, an input shaft, and reduction gearing extending between said input and output shafts, said input shaft and reduction gearing being carried by said llpper sweep arm.

PHILIP H. WOODS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 143,665 Butler Oct. 4, 1873 482,300 Cook Sept. 6, 1892 567,811 Lefevre Sept. 15, 1896 653,704 ,Scott July 17, 1900 1,050,729 Ford Jan. 14, 1913 1,136,252 Meier Apr. 20, 1915 1,239,165 Davis Sept. 4, 1917 1,381,686 Whigelt June 1.4, 1921 1,528,694 Riley Mar. 3, 1925 1,657,331 Witherow Jan. 24, 1928 1,662,131 Schoneld Mar. 13, 1928 FOREIGN PATENTS Number Country Date 8,916 Great Britain Apr. 10, 1911 266,761, Germany Oct. 30, 1913 

